A cyclone separator, sometimes referred to as centrifugal separator, works by putting a fluid in a rotational movement so that centripetal forces can operate in order to separate the fluid in a heavy part and a lighter part. The fluid will typically follow a helical phase and the heavy parts, phases or components will be collected at the outer peripheral of the helical path, while the lighter parts, phases or components will be collected along the longitudinal axes. In practical separation devices gravitational forces are often used together with a rotational movement, where heavy components can be drained or flowing down by means of gravitational forces, while lighter components may rise.
Centripetal force is the force that forces the fluid into a helical path. The centripetal force is proportional to the mass so that the phases or components will have difficulty in following the helical path, which explains why heavy components will be collected in the outer peripheral of the helical path. The centripetal force is however also proportional to the velocity in square, that being path speed in meter per second or angular speed. Higher speed provides a more efficient rotational movement and accordingly better separation. In connection with the above it is commonly recognized for a person skilled in the art that the separation efficiency increases with the flow rate. However, it has been shown that the separation efficiency sometimes is considerably reduced compared to the expected. The reduced separation efficiency is particularly evident at high pressure and high flow rates.
In the Soviet documents SU 1 445 763 A1 and SU 837369, there are however disclosed separation devices that partly solved the above problems in that separation devices where fluid can be filtered from a gas flow have been described. The filters are sleeve formed, there is no gas flow through the filters, the volume outside the filters is not open towards a gas discharge and the separation units appear to have only a narrow operating range in which the separation efficiency is particularly good.
Therefore there is a need in the art to provide a separation device with high separation efficiency in a wide range of operation conditions, including relatively high pressure and high flow rates.